Xuesen Fan, Meng Yan, Yuanyuan Wang
Oct 21, 2015
Citations
0
Influential Citations
17
Citations
Journal
The Journal of organic chemistry
Abstract
An efficient and convenient synthesis of pyrazolo[5,1-a]isoquinolines has been achieved via palladium-catalyzed Sonogashira coupling of terminal alkynes with 5-(2-bromophenyl)-1H-pyrazoles, in situ formed from the condensation of 1-(2-bromophenyl)buta-2,3-dien-1-ones with hydrazine hydrate, followed by 6-endo intramolecular alkyne hydroamination. More interestingly, 8-methylenepyrazolo[5,1-a]isoindoles, the regioisomer of pyrazolo[5,1-a]isoquinolines, could also be selectively synthesized from the same starting materials through an initial intermolecular hydroamination of terminal alkynes with 5-(2-bromophenyl)-1H-pyrazoles followed by a palladium-catalyzed 5-exo intramolecular Heck coupling reaction.